Internal combustion engine and a method for operating an internal combustion engine

Abstract

A controller configured to control a gas mixing device and/or a port injection valve and a direct fuel injector of an internal combustion engine in order to:in a first operation mode, supply a first gaseous fuel to at least one main combustion chamber of the internal combustion engine via at least one intake valve,in a second operation mode, supply a second gaseous fuel to the at least one main combustion chamber of the internal combustion engine by use of the direct fuel injector,wherein a supply system for providing flushing gas to the direct fuel injector is provided and the controller is configured to activate the direct fuel injector during operation according to the first operation mode, such that the flushing gas is injected into the at least one main combustion chamber.

1 . A system, comprising:
 a controller configured to control a supply of fluids to at least one main combustion chamber of an internal combustion engine to:
 in a first operation mode, supply a first fuel to at least one main combustion chamber of the internal combustion engine via at least one intake valve; 
 in a second operation mode, supply a second fuel to the at least one main combustion chamber of the internal combustion engine via a fuel injector; and 
 activate the fuel injector in the first operation mode to supply a flushing gas into the at least one main combustion chamber during an exhaust stroke of the internal combustion engine. 
   
     
     
         2 . The system of  claim 1 , wherein the controller is configured to supply the flushing gas comprising fuel during the exhaust stroke to cause combustion of the fuel in an exhaust manifold to increase an exhaust temperature of an exhaust gas. 
     
     
         3 . The system of  claim 2 , wherein the combustion of the fuel in the exhaust manifold is configured to increase the exhaust temperature of the exhaust gas for a selective catalytic reduction (SCR) converter. 
     
     
         4 . The system of  claim 2 , wherein the controller is configured to supply the flushing gas comprising the fuel that provides maximally 30% of the overall energy released during the combustion cycle during the first operation mode. 
     
     
         5 . The system of  claim 1 , wherein the controller is configured to supply the flushing gas via the fuel injector only during a cycle when the fuel injector is not used for fuel injection. 
     
     
         6 . The system of  claim 5 , wherein the controller is configured to supply the flushing gas via the fuel injector only during the first operation mode when the fuel injector is not used for fuel injection of the second fuel. 
     
     
         7 . The system of  claim 5 , wherein the flushing gas excludes fuel. 
     
     
         8 . The system of  claim 7 , wherein the controller is configured to supply the flushing gas that excludes fuel in a mass that is maximally 50% of an overall fuel mass supplied to the at least one main combustion chamber during a combustion cycle during operation according to the first operation mode. 
     
     
         9 . The system of  claim 8 , wherein the flushing gas comprises an inert gas, air, or a combination thereof. 
     
     
         10 . The system of  claim 1 , wherein the controller is configured to supply the flushing gas via the fuel injector for cooling and removing deposits from the fuel injector during the first operation mode when first fuel is used for combustion, after the fuel injector previously injected the second fuel for combustion in an earlier cycle. 
     
     
         11 . The system of  claim 10 , wherein the second fuel comprises hydrogen. 
     
     
         12 . The system of  claim 1 , comprising the internal combustion engine coupled to the controller. 
     
     
         13 . The system of  claim 1 , comprising a mixer, an injection valve, or a combination thereof, configured to supply the first fuel to the at least one main combustion chamber via the at least one intake valve. 
     
     
         14 . The system of  claim 1 , wherein the first fuel comprises natural gas and the second fuel comprises hydrogen. 
     
     
         15 . A system, comprising:
 a controller configured to control a supply of fluids to at least one main combustion chamber of an internal combustion engine to:
 in a first operation mode, supply a first fuel to at least one main combustion chamber of the internal combustion engine via at least one intake valve; 
 in a second operation mode, supply a second fuel to the at least one main combustion chamber of the internal combustion engine via a fuel injector; and 
 activate the fuel injector in the first operation mode to supply a flushing gas into the at least one main combustion chamber only during a cycle when the fuel injector is not used for fuel injection. 
   
     
     
         16 . The system of  claim 15 , wherein the controller is configured to supply the flushing gas via the fuel injector only during the first operation mode when the fuel injector is not used for fuel injection of the second fuel. 
     
     
         17 . The system of  claim 15 , wherein the flushing gas excludes fuel, and wherein the flushing gas comprises an inert gas, air, or a combination thereof. 
     
     
         18 . A system, comprising:
 a controller configured to control a supply of fluids to at least one main combustion chamber of an internal combustion engine to:
 in a first operation mode, supply a first fuel to at least one main combustion chamber of the internal combustion engine via at least one intake valve; 
 in a second operation mode, supply a second fuel to the at least one main combustion chamber of the internal combustion engine via a fuel injector; and 
 activate the fuel injector in the first operation mode to supply a flushing gas into the at least one main combustion chamber for cooling and removing deposits from the fuel injector during the first operation mode when first fuel is used for combustion, after the fuel injector previously injected the second fuel for combustion in an earlier cycle. 
   
     
     
         19 . The system of  claim 18 , wherein the second fuel comprises hydrogen. 
     
     
         20 . The system of  claim 19 , wherein the controller is configured to supply only the first fuel and air to the at least one main combustion chamber via the at least one intake valve and only the flushing gas to the at least one main combustion chamber via the fuel injector during the first operation mode, wherein the controller is configured to supply only the second fuel to the at least one main combustion chamber via the fuel injector during the second operation mode.